Surface grinder



Patented July 7, 1942 UN ITED: STAT E Si Pf"A IQCE.;

SURFACE GRINDER Theodore 1V. Ragsdale, Jr., Los Angeles; Calif. Application Novembem, 1940; serialfNo. v364,619

(Granted under thegact of MarchyS. 1883, as

amended Aprilf130,,1928; 3705'0. G. 757) 8 Claims.

This invention described herein may be'manufactured and used'by or for theGovernmentfor governmental purposes, without'the paymentA to me of any royalty thereon.

This invention `relates to' a surface grinder,

more. particularly it is directed to a deviceofthis character for grinding or otherwise nishing metalliciandtother surfaces.

Onepfthejobjects of the invention is to provide a` surface grinder adapted to be readily moved over asurface by the Vhand and'including a motor,V a" grinding member operated' by'the motor and Aa `supporting'member therefor which is `adapted toihold' the `motor'and grinding member.` in aj xedfsteady adjusted position thereon and to guidethegrin'ding member over the surfaceA4 to be'ground or' otherwise finished.

Another olojectof the invention islto provide a surfacegrinder whichis rigidin construction, easy to operate, which will give satisfactory service overalong'period` oftime and sodesigned as togreachallv corners.` walls and'places which may-be `inaccessible 'to other'surface grinders of IiKecharaCter; i

Brieflystated,` the improved surface grinder comprises a supportiadapted to movably` seat on a surface andhaving a' hand gripping portion thereon adapted to be grasped by the handfor movingthe grinder to different positions on the surfacegja guide member adjustably mounted on thesupport,Y a `carrier member slidably` and adjustablyA mounted on the guidey member, means for ,adjustably actuating the carrienmember on the `guidemember,V and a motor operated grinder rotatably Land longitudinally adjustably mounted onthe carrier member, whereby the motor operated grinder may be manually moved to differentpoints on asurface to be ground,4 adjusted to` various positions for engagement with awork piece andheldin a fixed steady position during a grinding operation. A handle extension adapted Atobe detachably connected to the hand 'grippingrportion of the support to prevent the user ofthe device fromV leaning over duringagrind- Fig. 2 is a fragmentaryviewof the other. side of the surfacegrinder;

Fig. 3 is an enlarged fragmentary detailv sectiontaken on the line 3-3 of Fig. 2;

Fig. 4 is an enlargedvertical sectional view` taken on the `line 4-4 of Fig. 2;

Fig. 5Yis a fragmentary detail sectionalview partly inelevation ofV a hand gripping pOrtionand a portion of the handle extension detachably secured thereto; taken on the line 5-5 of Figs'l, and,`

Fig. 6 is a side elevationof a guide` memlber used in carrying out the invention.

In the illustrated embodiment characterizing the invention I designates a support comprising a fiat vertically extendingrbody portion 2 having a base or foot portion 3 which is adapted to lie fiat on a surface 4 to be ground or otherwise finished and may be provided with oall bearings 5 mounted thereon in any suitable manner, whereby the device may be freely moved to different positionsvon the surface 4.

On one side of the body portion 2 of the support I is'a guide memberl 6 containing an openl T-shaped or undercut channel l, as illustrated in-Fig.r 4,A and having spacedlugs or ears IlY rectangular in cross-section projecting outwardly from onefside thereof, as more particularly illustrated in'Fig. 6. The guide member Gis longitudinally arranged on thev body portion 2 of the support and extends outwardly at right angles from'one side thereof with the lugs 8 projecting into spaced vvertically extending elongated apertures 9 provided in the body portion 2 of the support and with the inner side portion Il] of the guide member intermediate the lugs 8; abutting against a portion ofthe surface of the body portion 2 between the apertures 9, as illustrated in Fig. 3.

The guide member 6 is vertically adjustably mounted on the-body portion 2 of the support by meansof an elongatedfrectangular shaped side plate II carrying spaced set screwsfl'. which are,

adapted to threadably engage at theirinner ends in threaded holes or wells I3 formed in the free.

ends of the lugs 3 of the guide member. The

side plate I I also carries a set 'screw` I4 at its cen-V tral portion which is adapted to abut at its inner end against the outer surface of the body portion on the opposite side thereof from the guide member, as illustratedin Fig. 3. By tightening up on the set screw I4 the side plate Ill is forced from the side of the bodyportion of the support thereby causing the side plate to moresecurely y hold the guide member in .its adjusted position against the body portion. A washer I5 or the like may be provided on the screw I4. The guide member 6 is adapted to slidably support a longitudinally extending carrier member I6 which is substantially rectangular shaped in cross section and having a longitudinally extending bore I1 formed therein and a downwardly extending portion I8 which is adapted to engage in the T- shaped or undercut channel 1 formed in the guide member 6.

The carrier member I6 is adapted to be moved longitudinally on the guide member 6 by means of an elongated adjusting screw I9 which is rotatably secured at its head 2|), as illustrated in Fig. 1 in an upwardly extending base portion 2| provided on the rear end of the guide member 6. The free end of the adjusting screw I9 projects into and threadably engages a threaded opening 22 longitudinally formed in the lower Iportion of the carrier member. By turning the head 20 of the adjusting screw I9 in either direction with a wrench or the like, the threads on the adjusting screw engaging with the threads of the opening 22 in the carrier member will cause the `carrier member to be moved longitudinally forward or backward on the guide member. In order to lock the screw I9 in an adjusted position, a lock nut 23 is theradably mounted on the screw at the opposite side of the base portion 2| from the head 26 of the screw and to hold the carrier member I6 in an adjusted position on the guide member 6, a set screw 24 is provided which is threadably mounted on the guide member and adapted to Contact with the carrier member at its inner end.

A motor 25 having a grinder shaft 26 containing a grinding member 21 on its outer end is longitudinally and rotatably adjustably mounted on the carrier member I6 by means of a horizontally extending arm or shaft 28 xedly mounted on one side of the motor. The arm or shaft 28 extends from the motor at a right angle to the grinder shaft 26 and is adapted to rotatably and longitudinally engage in the bore I1 of the carrier member. Set screws 29 arranged at suitable points on the carrier member I6 are provided which are adapted to contact at their inner ends with the outer peripheral surface of the arm 28 of the motor whereby the motor 25 and grinding member 21 may be locked in an adjusted position on the carrier member. The motor 25 is preferably of the electric type and has feed wires or conductors 30 leading to a suitable source of electrical supply (not shown) and the grinding member 21 is illustrated as an emery stone for removing high spots in a metallic or other surface.

The upper rear end of the body portion 2 of the support is provided with `a hand gripping portion 3| including a nger engaging slot 32 whereby the device may be grasped by the hand to direct the grinding member 21 to different positions on the surface to be ground.

To prevent the user of the device when desired from leaning over to move it to different positions over a piece of work, a handle extension 33 is provided which may be detachably secured to the hand gripping portion 3| on the support I, as illustrated in Fig. 1. The handle extension 33 is provided with an end portion 34 having a projection 35 thereon preferably of metal, which is adapted to engage a portion of one sideof the hand gripping portion 3i and bent at its free end to provide a portion 36 at a right angle to the body of the projection and a portion 31 at a right angle to the portion 36 so that it may be inserted in an opening or slot 38 provided on the hand gripping portion 3| on the body portion 2 of the support with the portion 36 abutting against the inner edge of the slot 38 and the portion 31 abutting against the other side of the hand gripping portion 3| from the body of projection 35. The end portion 34 of the handle extension 33 is detachably held in place on the hand gripping portion 3| of the support by means of a plate 39, preferably of metal, which is positioned on the opposite side of the hand gripping portion from the projection 35 and held in pla-ce thereon by a bolt 40 which extends through the finger engaging slot 32 on the hand gripping portion and bolted to the -projection 35 by a nut 4I, as illustrated in Fig. 5. This end portion 34 of the handle extension 33 extends upwardly at an angle from the hand gripping portion 3| and is detachably connected at its outer end to the inner end of the handle extension by the bolt 42 and hand lever 43.`

In using the surface grinder on the surface 4 and assuming that current is turned on into the electrical motor 25 from the source of electrical supply (not shown) through the conductors 30, the motor will turn the grinder shaft which in turn will revolve the grinding member 21 at a high rate of speed over the surface 4 whereby the surface is ground down to an even surface or otherwise finished. When it is necessary to move the surface grinder to a different point or should a high point on the surface 4 be encountered, the set screw I4 on the side plate II is unscrewed an amount to release the outward pressure on the side plate and the set screws I2 on the side plate are unscrewed from the threaded holes' I3 in the lugs 8 of the guide member 6, an amount to permit the guide member to be raised by the hands in a vertical or perpendicular direction with the lugs 8 on the guide member sliding in the vertical extending aper- .tures 9 in the body portion 2 of the support,

whereby the carrier member I6, the motor 25 and grinding member 21 mounted thereon are also raised to the required height in a vertical or perpendicular direction. The set screws I2 and the screw I4 on the side plate II are then tightened up by a wrench, or the like and the surface grinder moved to the proper position by grasping the hand gripping portion 3| on the Ibody portion 2 of the support or by means of the handle extension 33 where the set screws I2 and the screw I 4 are again unscrewed to permit the guide member 6, the carrier member I6, the motor 25 and grinding member 21 to be moved downwardly and thus permit the grinding member to again contact with the surface, in which case the set 4screws I2 and the screw I4 are again tightened.

Should it be desired to grind a surface which is not horizontal the guide member 6 and the parts supported thereon are again raised to a predetermined height and the set screws 29 on the cartated a predetermined amount on the carrier member the set screws 29 are again tightened to hold the motor and grinding member in their adjusted position. To move the carrier member I6, carrying the motor 25 and the grinding member 2l in a forward or rearward direction on the support I the adjusting scew I9 on the guide member 6 is actuated as above described.

It will thus be seen that there is herein provided a novel and eflicient form of surface grinder which is well adapted for all the purposes indicated. Even though there has been herein shown and described certain features of construction and operation of parts, it is nevertheless to be understood that various changes may be made therein if the changes do not depart from the claims.

Having described my invention, what I claim as new and wish to secure by Letters Patent is:

1. In a surface grinder, the combination of a support including a base portion and a body portion, apertures formed in said body portion, a guide member cooperating with said apertures and adjustably mounted vertically on the body portion, a carrier member slidably mounted on said guide member and a motor operated grinder adjustably mounted on said carrier member.

2. In a surface grinder, the combination of a support including a base portion and a body portion, apertures formed in said body portion, a guide member cooperating with said apertures and adjustably mounted vertically on the body portion, a carrier member slidably mounted on` the guide member, means for slidably actuating the carrier member on said guide member and a motor grinder unit adjustably mounted on said carrier member.

3. In a surface grinder, the combination of a support including a base portion and a body portion, apertures formed in said body portion, a guide member having a channel formed therein, said guide member cooperating with said apertures and adjustably mounted vertically on the body portion, a carrier member including a portion slidably mounted in the channel of said guide member and a motor grinder unit slidably and rotatably mounted on said carrier member.

4. In a surface grinder, the combination of a support including a base portion and a body portion, apertures formed in said body portion, a guide member cooperating with said apertures and adjustably mounted vertically on the body portion, a carrier member slidably mounted on .said guide member, a motor including means longitudinally and rotatably mounted on said carrier member and a grinding member actuated by said motor.

5. In a surface grinder, the combination of a support including a base portion and a body portion having a hand gripping portion provided thereon, apertures formed in said body portion, a guide member cooperating with said apertures and adjustably mounted on said body portion, a carrier member slidably mounted on the guide member, a motor, a Xed shaft on said motor longitudinally and rotatably mounted on said carrier member and a grinding member actuated by said motor.

6. In a surface grinder, the combination of a support including a base portion and a body portion having a hand gripping portion thereon, apertures formed in said body portion, a guide member cooperating with said apertures and adjustably mounted on the body portion, a carrier member slidably mounted on the guide member, a motor grinder unit rotatably and longitudinally adjusted mounted on said carrier member and a handleextension detachably connected to the hand gripping portion of said body portion.

7. In a surface grinder, the combination of a support including a base portion and a body portion, apertures formed in said body portion, a guide member cooperating with said apertures and adjustably mounted on the body portion, a carrier member containing a bore slidably and adjusably mounted on said guide member, a motor, a fixed arm projecting from said motor, said arm longitudinally and rotatably mounted in the bore of said carrier member, a grinder shaft operated by said motor, and a grinding member mounted on said grinder shaft, said grinder shaft being at a right angle to the fixed arm on said motor` 8. In a surface grinder, the combination of a support including a base portion and a body portion containing vertically extending apertures, a guide member having lugs projecting outwardly therefrom, vertically adjustable on the body portion, said lugs on the guide member slidably mounted in the apertures in the body member, a side plate adjustably bolted to the lugs on the guide member, a carrier member slidably and adjustably mounted on the guide member, means for adjustably actuating the carrier member on said guide member, and a motor grinder unit longitudinally and rotatably adjustably mounted on said carrier member.

THEODORE V. RAGSDALE, JR. 

